CAS said Wednesday that international track rules supposedly designed to reduce naturally high testosterone levels in some female runners “are discriminatory” – its words, not mine. And CAS is absolutely right.

Semenya, a two-time Olympic champion in the 800 meters who blisters the track every time she steps on it, is believed to be intersex. She did not choose this condition, any more than Michael Phelps chose his inordinately wide wing span or Usain Bolt chose his considerably long legs. It is as much a part of Semenya’s biological makeup as the color of her eyes, skin and hair.

Unfortunately, CAS didn’t stop there. It went on to say that while it had concerns about how the International Association of Athletics Federations (IAAF) would implement these rules, they were “a necessary, reasonable and proportionate means of achieving the legitimate objective of ensuring fair competition in female athletics in certain events.”

In other words, discrimination is wrong – unless it’s being used against women like Semenya.

“I know that the IAAF’s regulations have always targeted me specifically,” Semenya said in a statement. “For a decade the IAAF has tried to slow me down, but this has actually made me stronger.”

Set aside for the moment the fact that the IAAF used questionable science to create and defend its rules. Or that levels of testosterone, like every other hormone, rise and fall based on other aspects of biology. And that, by only applying these rules to only select distances, the IAAF left no doubt that it was trying to limit Semenya’s success because her competitors cannot.

At the heart of this issue is fairness.

“It is not possible to give effect to one set of rights without restricting the other set of rights,” CAS said in announcing its decision.

Yet this is exactly what the CAS decision did. By saying Semenya, and other women like her, must mute their innate biology and medicate to suppress testosterone in order to compete, CAS is giving preference to those women who don’t have to.

But where does that stop?

Can you imagine barring Phelps from the Olympics because his hands and feet were too large and his arms too long? If Senegal’s men’s basketball team qualifies for the 2020 Summer Games in Tokyo, are we to tell Tacko Fall he’s ineligible because, at 7-6, he will tower over his competitors and be too hard for some to guard? What of gymnasts who are double-jointed, making it easier to do certain skills on the uneven and parallel bars?

We cannot cheer the biological advantages some athletes have – Phelps again – while penalizing those of others. Every body is different, and trying to parse out what is acceptable and what is not, what percentage of success is genetics and what is training, nutrition and determination, will take us down a dangerous road.

“Ms. Semenya believes that women like her should be respected and treated as any other athlete,” Semenya’s lawyers said in a statement. “As is typically the case across sport, her unique genetic gift should be celebrated, not regulated.”

CAS decided that the IAAF’s rules were discriminatory. That should have been the end of the debate.